Within a speaker, pulses of electricity are typically passed through a voice coil positioned in proximity of a permanent magnet. As the magnetic field generated by the voice coil rapidly changes along with received current pulses of varying magnitude, the voice coil is attracted to and repelled from the permanent magnet. These vibrations of the voice coil are amplified by the motion of a speaker membrane that moves in and out to pump sound waves into the air. In general, speaker volume is proportional to the excursion range of the speaker membrane, and sound quality is impacted by the evenness of movement of the speaker membrane toward and away from the magnet. Rigid movement—like a piston—tends to provide higher sound quality while movement that is less even (e.g., wobbling due to poor membrane suspension) reduces sound quality.
In traditional large speakers, a flexible, corrugated support called a spider is used to suspend the voice coil in place within a basket housing. In a different variant, the spider can attach to the membrane (e.g., diaphragm) on one side and a basket or magnet on the other side, providing stabilization for the membrane throughout its corresponding range of motion. In contrast to these traditional large speakers, modern mini and micro speakers tend to feature thinner membranes that better respond to the flux ranges of smaller magnets. Often, the compact arrangement of mini and micro speakers does not permit a spider to be included to stabilize the membrane because, in many cases, the traditional location of the spider is occupied by magnet material as a result of spacing constraints.